Search for Pair Production of Heavy Vector-Like Quarks Decaying to High-P_T W Bosons and B Quarks in the Lepton-Plus-Jets Final State in PP Collisions at √s=13 TeV with the ATLAS Detector

Aaboud, M.Aad, G.Abbott, B.Abdinov, O.Abeloos, B.Abidi, S. H.AbouZeid, O. S.Izen, Joseph M.Meirose, BernhardReeves, Kendall2018-09-122018-09-122017-10-202017-10-201126-6708http://hdl.handle.net/10735.1/6065A search is presented for the pair production of heavy vector-like T quarks, primarily targeting the T quark decays to a W boson and a b-quark. The search is based on 36.1 fb⁻¹ of pp collisions at √s=13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Data are analysed in the lepton-plus-jets final state, including at least one b-tagged jet and a large-radius jet identified as originating from the hadronic decay of a high-momentum W boson. No significant deviation from the Standard Model expectation is observed in the reconstructed T mass distribution. The observed 95% confidence level lower limit on the T mass are 1350 GeV assuming 100% branching ratio to Wb. In the SU(2) singlet scenario, the lower mass limit is 1170 GeV. This search is also sensitive to a heavy vector-like B quark decaying to Wt and other final states. The results are thus reinterpreted to provide a 95% confidence level lower limit on the B quark mass at 1250 GeV assuming 100% branching ratio to Wt; in the SU(2) singlet scenario, the limit is 1080 GeV. Mass limits on both T and B production are also set as a function of the decay branching ratios. The 100% branching ratio limits are found to be applicable to heavy vector-like Y and X production that decay to Wb and Wt, respectively.enCC BY 4.0 (Attribution)©2016 CERN, for the ATLAS Collaborationhttp://creativecommons.org/licenses/by/4.0/QuarksW bosonsProton-proton interactionsLeptons (Nuclear physics)Jets (Nuclear physics)Hadrons—DecayStandard model (Nuclear physics)Hadrons--ScatteringSearch for Pair Production of Heavy Vector-Like Quarks Decaying to High-P_T W Bosons and B Quarks in the Lepton-Plus-Jets Final State in PP Collisions at √s=13 TeV with the ATLAS DetectorarticleAaboud, M., G. Aad, B. Abbott, et al. 2017. "Search for pair production of heavy vector-like quarks decaying to high-p_T W bosons and b quarks in the lepton-plus-jets final state in pp collisions at √s=13 TeV with the ATLAS detector." Journal of High Energy Physics 2017(10), doi:10.1007/JHEP10(2017)141201710